Prolonged sitting causes tight Psoas muscles, which makes pelvis to tilt anteriorly and cause pain in the back.
Improper standing or sitting postures cause the spine to move away from the neutral position, which give rise to back pain through the muscle imbalances introduced in the body. This happens because the muscles adapt to the skeletal postures that they are subjected to. For example, if your job requires you to sit at a desk or computer all day, you could develop a forward head posture where the chest and shoulder muscles become tight, and the hip muscles get weak and pull the spine out of alignment. Proper flexibility and strengthening of these muscles will prevent muscle imbalances that underlie these conditions.
The Iliopsoas Muscle
Learning how the placement of pelvis affects various muscles help us to balance the spine.
Although there are many muscles that are considered to be “flexors” of the hip, the two muscles that are most commonly thought of as “The Hip Flexors” are the Illicacus and Psoas (often referred to as one muscle — the illiopsoas).
The Psoas is shortened when you are seated and will become tight & contracted when seated for a prolonged period of time.
Please watch the following video which explains the iliopsoas muscles and gives simple exercises to strengthen the hip.
This test is to determine if you have a tight psoas or tight hip flexors.
Why Does tight Psoas Cause Back Pain?
The psoas attaches on all five lumbar vertebrae and is responsible for flexing the thigh at the hip joint. The psoas muscles lie behind the abdominal contents, from the lumbar spine to the inner thighs near the hip joints ; the abdominal muscles lie in front of the abdominal contents, from the lower borders of the ribs (with the rectus muscles as high as the nipples) to the pubic bone. Tight psoas muscles, which lie behind the abdominal contents, pull the spine forward and push the abdominal contents forward, causing protrusion and moving you into an anterior tilt or lordotic posture. The tension exerted by the Psoas when in a contracted state may compress the joints and discs of the lumbar vertebrae. This pressure may cause degeneration and increase susceptibility to injury. As the Psoas and portions of the Gluteal muscles function as opposing muscles, a tight Psoas may inhibit your Gluteal muscles from firing and activating normally.
Here is a great activation exercise that activates and also connects the glute to the opposite hip flexor (psoas).
Strengthen with the Supine Bridge
Lie face-up on the floor with your knees bent and your feet flat. Focus on drawing your belly button to your spine to activate the transverse abdominal muscle. Then lift your hips until your body forms a straight line from the base of your neck to your hips to your knees. Concentrate on contracting your glutes, not your hamstrings, to extend your hips to neutral. Hold the position for 10 seconds and then return to the starting position. Repeat six to 10 times.
Loosen with the Lunge Stretch
Kneel on your right knee and place your left foot on the floor in front of your body so that your left knee bends at a 90-degree angle. Draw your navel toward your spine and roll your pelvis backward. Put your weight forward into the lunge until you feel a stretch in your right hip flexors (located where your thigh joins your pelvis). Be sure to keep your left knee in line with your left ankle. Hold the stretch for 20 seconds and then repeat on the other side.
Here are some more exercises to relax the tight Psoas muscles.